Ultra-stable fluoropolymer glasses were created using vacuum pyrolysis deposition that show large fictive temperature Tfreductions relative to the glass transition temperature Tgof the rejuvenated material. Tfwas also found to be 11.4 K below the dynamic VFT temperature TVFT. Glass films with various thickness (200–1150 nm) were deposited onto different temperature substrates. Glassy films were characterized using rapid-chip calorimetry, Fourier-transform infrared spectroscopy and intrinsic viscosity measurements. Large enthalpy overshoots were observed upon heating and a Tfreduction of 62.6 K relative to the Tgof 348 K was observed. This reduction exceeds values reported for a 20-million-year-old amber and another amorphous fluoropolymer and is below the putative Kauzmann temperature TKfor the material as related to TVFT. These results challenge the importance of the Kauzmann paradox in glass-formation and illustrates a powerful method for the exploration of material dynamics deep in the glassy state (Tf < T < Tg).
Ultra‐stable amorphous fluoropolymers glasses were created using vacuum pyrolysis deposition (VPD). Glass films with thickness ranging from 90 to 160 nm were grown at a substrate temperature of 0.86
- NSF-PAR ID:
- 10483498
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 62
- Issue:
- 1
- ISSN:
- 2642-4150
- Format(s):
- Medium: X Size: p. 102-114
- Size(s):
- ["p. 102-114"]
- Sponsoring Org:
- National Science Foundation
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